Alarm clock



I 1944- M. E. SCHLENKER I 7 2,360,589

ALARM CLOCK Filed Sept. 4', 1943 IN V EN TOR.

A TTORNEY.

MAX E. SCHLENKEE Patented Oct. 17, 1944 UNITED STATES PATENT OFFICE ALARM CLOCK Application September 4, 1943, Serial No. 501,228

6 Claims.

The present invention relates in general to alarm clocks. The main object of the invention is to provide an improved alarm mechanism and control means therefor which are extremely simple and economical to manufacture. According to one feature of the invention the alarm hammer mechanism is moved into and out of engagement with the trip spring to provide manual control of the alarm.

Another feature of the invention resides in the utilization of the trip spring as a sounding medium for the alarm hammer.

A clear understanding of the above and other features of the invention not specifically mentioned and of the operation of the improved alarm mechanism may be had from the following description when read in connection with the accompanying drawing, comprising Figs. 1 to 3, inelusive, in which Fig. 1 is a top view of a portion of an alarm clock movement showing the improved alarm mechanism of the present invention;

Fig. 2 is a front elevational view of the mechanism shown in Fig. 1; and

Fig. 3 is a top view of the trip and shut-off mechanism with the parts in a position different from that shown in Fig. 1.

Referring in detail to the drawing, only sufiicient of the clock mechanism has been shown to enable one to obtain a clear understanding of the present invention. Thus the escapement mechanism and the time train have been omitted entirely since these may be standard and do not concern this invention.

The alarm mechanism as well as the time train is mounted between a back movement plate I and a front movement plate 2 which are held together in spaced parallel relationship by means of pillars 3. Journalled in the two movement plates is the usual minute hand shaft 4 which is geared to the usual time train (not shown). This shaft extends through the back cover plate 19 and terminates in the time setting knob 5. Rigidly attached to the shaft 4 in front of the front movement plate 2 is the shuck pinion 6 which is in engagement with the motion wheel I. The motion wheel 1 and the motion wheel pinion 8 are fastened together and are rotatably mounted on a stub shaft in the front movement plate. The motion Wheel pinion 8 is in engagement with the alarm trip wheel 9 and with the hour wheel I! mounted on the hour sleeve 18. The sleeve I8 is rotatably mounted on the minute hand shaft 4. The alarm trip wheel 9 and the associated trip wheel bushing I: are rotatably mounted on the alarm set shaft 52 which is journalled in plates I and 2 and extends through the back cover 59, terminating in the alarm set knob l3.

Fixedly mounted on the alarm shaft I2 is the alarm trip cam l5. Also mounted on the shaft [2 is the usual alarm set indicator hand which cooperates with an alarm set dial (not shown) A friction spider I4 is provided to prevent accidental or inadvertent rotation of the shaft l2. The alarm trip cam 15 is provided with the usual notched out portion which cooperates with the trio finger it struck out from the surface of the alarm trip wheel 9.

Mounted on the front of the front movement plate by means of screw in is the alarm trip spring 2e terminating in a laterally extending projection 2!. The other end of this trip spring is bent over and extends to the back cover plate l9, this portion having a reduced end which fits into a hole into the back cover.

Also journalled between the movement plates l and 2 is a shaft which mounts the hammer mechanism. The alarm hammer 24 is mounted on a lever 23, one arm of which terminates in a bent over portion 22 adapted to cooperate with the projection 2! on the trip lever 29. Struck out from the lever 23 at right angles thereto are the two pallets 30 and 3! which engage the alarm escape wheel 32.

Mounted on the rear end of the shaft 25 is the alarm switch knob 28 by means of which the shaft 25 and associated mechanism may be shifted axially to turn the alarm on and off. A split washer 29 is provided on shaft 25 to limit the rearward movement of this shaft. The shaft is also provided with two grooves 25 which are engaged by a positioning spring 2'! so that the shaft is retained in either one of two definite positions. The alarm escape wheel 32 and the associated lantern pinion 35 are mounted on a shaft 33 journaled in the front and rear movement plates.

The pinion 35 is in engagement with the alarm main wheel 38 rotatably mounted on shaft 37. Fixedly mounted on shaft 31 are the ratchet 38 and the friction washer 4!]. The alarm main wheel 36 is held between the ratchet 38 and the friction washer 49 and normally rotates therewith during the operation of the alarm mechanism.

A click 39 is provided having one end in engagement with the ratchet 38 and being retained in fixed relation to the alarm main wheel by means of projections which extend through the holes 44 and 45 in this wheel.

The shaft 31 extends through the back cover and terminates in an alarm winding key 42. One end of the alarm spring 4| is attached to the shaft 31 and the other end terminates in a loop surrounding the pillar 3.

When the key 42 is rotated to wind the spring 4|, the alarm main wheel 36 remains stationery and the click 39 slides over the teeth of the ratchet wheel 38. When the shaft is turned in the opposite direction by the alarm spring a tooth on ratchet 38 engages the clicks and rotates the alarm main wheel with the shaft.

Fig. 1 of the drawing discloses the alarm mechanism in its off position. The trip spring 2|! is held in its rearward position by means of the associated bushing and the hammer mechanism and lever 23 are held in their forward positions by means of the positioning spring 21 engaging groove 26. The alarm is set to go off at a predetermined time by means of the alarm set knob l3 in the usual manner. The trip wheel 8 is driven from the time movement and at the predetermined set time trip finger |6 drops into the notched out portion on a1arm trip cam l5. This permits the trip wheel and associated bushing to be moved forward by the trip spring 20. If the manual control switch is in off position the end 2| of the trip spring does not move far enough to disengage the laterally extending projection 22 of the hammer lever. However, if the manual control switch is in on position, as shown in Fig. 3 of the drawing, when the trip finger l6 engages the notch in the alarm trip cam the trip spring 29 moves forward and entirely disengages the projection 22. This frees the hammer lever and it is oscillated by the alarm spring 4| through the alarm main wheel 35, pinion 35, alarm escape wheel 32 and pallets 3i! and 3| which form a part of the hammer lever. During its oscillations the hammer 24 strikes extension 43 of the trip spring during each oscillation and sounds the alarm. In order to stop the alarm the manual control button 28 is depressed moving the hammer lever 23 forward so that it engages the projection 2| of the trip spring as shown by the dotted lines in Fig. 3. The engagement of projections 22 and 2| stops the oscillations of the alarm hammer lever 23. At a predetermined time after the time for which the alarm has been set, the continued rotation of the alarm trip wheel 9 again moves the trip finger I6 out of the notch in alarm cam l5 and the mechanism is then in its normal position as shown in Fig. 1.

From the foregoing it will be seen that the alarm mechanism disclosed herein is extremely simple and economical to manufacture. By means of this construction the numb-er of parts usually necessary for the alarm switch mechanism has been reduced and the usual alarm bell or gong has also been eliminated.

Although a preferred embodiment has been disclosed in the drawing and described in the specification, it will be apparent that modifications may be made by those skilled in the art without departing from the spirit of the invention as defined by the appended claims.

What is claimed is:

1. In an alarm clock, an alarm switch shaft, a lever on aid shaft having one arm terminating in an alarm hammer and a second arm terminating in a laterally extending projection, a trip lever having' a projection adapted to cooperate with said first projection, and means for axially shifting said shaft to bring said two projections into and out of engagement with each other.

2. In an alarm clock, an alarm switch shaft, a lever on said shaft having a hammer mounted thereon, means for oscillating said lever to sound an alarm, and means for axially shifting said shaft to silence said alarm.

3. In an alarm clock, alarm mechanism comprising an alarm hammer, means for oscillating said hammer to sound an alarm, a. trip lever normally engaging said hammer to render same inoperative, time mechanism for withdrawing said trip lever at a predetermined time to release said hammer, and means for shifting said hammer to re-engage said trip lever to again render said alarm mechanism inoperative.

4. An alarm mechanism for an alarm clock comprising an oscillatable member, means for oscillating said member to sound an alarm, a projection on said member, a trip lever having a projection adjacent said first projection, time controlled means for moving said trip lever to shift said second projection into and out of engagement with said first projection, and manual control means for shifting said oscillatable memher to move said first projection into and out of engagement with said second projection.

5. In an alarm clock, alarm mechanism comprising an alarm escape wheel, an alarm switch shaft, a lever on said shaft having one arm terminating in an alarm hammer, a second arm terminating in a blocking projection and two pallets adapted to engage the teeth of said alarm escape wheel, means for rotating said escape wheel to oscillate said lever to sound an alarm, and manual means for axially shifting said shaft to shut off said a1arm.

6. In an alarm clock, an alarm switch shaft, a lever on said shaft having a hammer at one end and a stop projection at the other end, means for oscillating said lever to sound an alarm, means for controlling said a1arm comprising a time-controlled trip spring adapted to cooperate with said projection and a manual control knob for axially shifting said shaft, and an extension on said trip spring lying in the path of said hammer and serving as a sounding medium therefor.

MAX E. SCI-ILENKER. 

